Voice over Internet protocol (VOIP) refers to a set of standards for communicating digitized voice in form of data over an IP-based network, such as the Internet. Current VOIP systems use different communication protocols, such as packet based telecommunication protocol H.323 and session initiation protocol (SIP), to set up calls between one or more communication endpoints. Each endpoint (e.g., communication device) may communicate over a different communication protocol, such that one endpoint may communicate over the H.323 protocol and another endpoint may communicate over the SIP, for example.
To support communication between endpoints that use different VOIP protocols, basic models for interworking the H.323 and SIP protocols have been implemented. Interworking refers to the process of mapping a communication method (or message) supported in one protocol to a corresponding or counterpart communication method (or message) in another protocol. Interworking thus provides for establishing a communication connection between two endpoints, even if one endpoint communicates over the H.323 and another endpoint communicates over the SIP, for example.
Unfortunately, not every communication message transmitted over a first VOIP protocol (e.g., H.323) can be mapped to a counterpart message in a second VOIP protocol (e.g., SIP). That is, a one-to-one mapping relationship does not necessarily exist for all messages across different protocols and communication platforms. For example, a 1xx provisional message in the SIP does not have a counterpart in the H.323; or the TCS/MSD message in the H.323 does not have a counterpart in the SIP.
Accordingly, a first message in a first protocol may not be mapped to what would be an equivalent or a corresponding message in a second protocol, if no counterpart for the first message exists in the second protocol. The inability to properly map messages between various protocols results in unreliable interworking and extra processing overhead for gateways and session border controllers (SBC) that provide the interworking capabilities.
For the above reasons, systems and methods are needed that can overcome the aforementioned shortcomings.
Features, elements, and aspects of the invention that are referenced by the same numerals in different figures represent the same, equivalent, or similar features, elements, or aspects, in accordance with one or more embodiments.